1. Field of the Invention
The present invention relates to a digital broadcast receiver and a directed channel change method thereof, in which a channel is changed according to directed channel change information transmitted from a broadcasting station.
2. Description of the Related Art
Digital broadcasting has recently begun. In digital broadcasting as compared with analog broadcasting, a video signal and an audio signal are converted into digital signals, and then the digital signal is compressed, packeted and transmitted as a transport stream.
Digital broadcasting standards are selected to be adapted to a variety of countries, respectively. A directed channel change table (DCCT) has been proposed as an extended standard of the program and system information protocol (PSIP) of the advanced television systems committee (ATSC) standard selected in North America. Further, there are similar standards for another digital broadcasting selected in Europe or other countries.
Here, the DCCT is a table, having information about how to automatically change a channel under certain conditions, which is transmitted in the PSIP. According to the DCCT, items taken as channel change conditions are tabulated by codes. For example, the item includes local information, population information, genre information, etc. Further, setting information corresponding to such items is set in a broadcast receiver by a user.
When a digital broadcast receiver receives DCCT information, the received DCCT information is compared with the previously set information related to the DCCT. In the case where the received DCCT information is equal to the previously set information related to the DCCT, the channel is changed according to the DCCT information. Then, when a program of the changed channel is finished, the channel returns to an original channel.
However, a plurality of virtual channels may be allocated to one channel number according to local characteristics. For example, in the case of an area located between Seoul and Daejeon in Korea, two channels corresponding to Seoul and Daejeon broadcasting stations may be allocated to one channel number of 11-1. Currently, the ATSC standard has no proposal to solve a problem of channel duplication.
Therefore, in this case, the digital television or a set-top box should select and change one of a plurality of duplicated channels to perform a directed channel change (DCC) function.